20050311

Macromolecular Quantum InterferenceViennaArndt, Hornberger and Zeilinger provide a summary of recent progress in matter-wave interferometry, outlining near-term experimental objectives as well as theoretical developments towards understanding the mechanisms of decoherence. "In our view, matter-wave interferometry should be feasible for large objects such as proteins, small viruses and nanocrystals with atomic masses of up to 10^6 units. Extrapolating our results to bigger masses and higher temperatures, we believe that neither collisions nor thermal decoherence will be a problem in these cases. No fundamental limit of quantum interference is yet in sight, but much work still has to be done to prepare and manipulate coherent beams of supermassive particles. Carrying out such experiments will be a fascinating challenge."

DARPA Quantum NetworkHarvard/Boston/BBN Chip Elliot reports on the current status of the DARPA Quantum Network, in continuous operation since June 2004. "The DARPA Quantum Network is the world's first quantum cryptography network, and perhaps also the first QKD system providing continuous operation across a metropolitan area. Four more nodes are now being added to bring the total to 10 QKD nodes." This paper updates quant-ph 0412029 for the upcoming SPIE conference.